Fucose

Squash (Guangmi No. 1) weighing 4.0–5.0 kg was harvested in July 2022 (Guangdong, China). To minimize differences, we selected squash that were the same size and had similar skin and flesh colors for treatment. After the squash was cleaned, the skin and seeds were removed. Next, the flesh of the squash was freeze-dried and crushed (100 mesh). Glucose, galactose, mannose, rhamnose, fucose, xylose, arabinose, glucuronic acid, galacturonic acid, 1,1-diphenyl-2-picrylhydrazyl radical (DPPH) and 2-2′-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) salt (ABTS) were purchased from Solarbio Technology Co., Ltd. (Beijing, China). α-Amylase (A-3176-500KU, 10 U/mg), pepsin (P6887-5 G, 3706 U/mg), pancreatin (P1750-100 G) and amyloglucosidase (A7420, 31.2 U/mg) were obtained from Sigma-Aldrich Corp. (St. Louis, MO, USA).

Black bean was provided by the Soybean Genetics and Breeding Group of Shanxi Agricultural University. Standard monosaccharides, including glucose, mannose, galacturonic acid, rhamnose, fucose, arabinose, and galactose, were purchased from Solarbio (Beijing, China). The other chemicals, including lipopolysaccharide (LPS), 1-phenyl-3-methyl-5-pyrazolone (PMP), trifluoroacetic acid (TFA), 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT), and concanavalin A (ConA) were obtained from Sigma-Aldrich (Shanghai, China).

The dry fruits (Ziziphus jujuba cv. Muzao) were provided by the Loess Plateau Experimental Orchard from Yulin in Shaanxi province, China. The chromatographic columns (DEAE-Sepharose Fast Flow and Sepharcyl S-300) were purchased from GE Healthcare Life Sciences (Piscataway, NJ, USA). The standards arabinose, fucose, galactose, glucose, mannose, rhamnose, and xylose were from Solarbio Life Sciences Co. (Beijing, China). The standards glucuronic acid and galacturonic acid were purchased from Aladdin Biochemical Technology Co., (Shanghai, China). All other chemicals were analytical grade.